In 2009, Congress gave the Food and Drug Administration wide authority to oversee tobacco products. The agency has moved cautiously in flexing that power. On Thursday, for the first time, the FDA "deemed" several tobacco products to be under its watch, including cigars, pipe tobacco, nicotine gels, hookahs and e-cigarettes. This move is welcome, if overdue. The FDA now has to conduct the tricky work of figuring out when further restrictions, particularly on e-cigarettes, help and when they might actually harm public health.

This editorial appeared in Friday's Washington Post.

In 2009, Congress gave the Food and Drug Administration wide authority to oversee tobacco products. The agency has moved cautiously in flexing that power. On Thursday, for the first time, the FDA "deemed" several tobacco products to be under its watch, including cigars, pipe tobacco, nicotine gels, hookahs and e-cigarettes. This move is welcome, if overdue. The FDA now has to conduct the tricky work of figuring out when further restrictions, particularly on e-cigarettes, help and when they might actually harm public health.

As long as the FDA steers clear of direct regulation of products other than cigarettes, smokeless tobacco and roll-your-own tobacco, public health advocates rightly worry that potential smokers — particularly children and teenagers — will find it easier or more appealing to use unregulated products with varying or unknown public health effects. The agency says that expanding its oversight, which Congress gave it the power to do, is the first, "foundational" step toward broad regulation of these alternatives to cigarettes.

The FDA is demanding some concrete steps of manufacturers upfront. They will have to register their products with the agency and reveal their ingredients. They will have to attach warning labels. Many vending machines will become off-limits. And the federal government will ban e-cigarette sales to minors. Once regulators gather more information on the harm various products can cause and on how people are obtaining and using them, they can do more in the interest of public health, such as consider bans on Internet sales, candy-like flavorings or certain kinds of marketing.

The FDA is also accepting feedback on whether to exempt "premium" cigars from regulation, since people often do not smoke them habitually. That strikes us as unnecessary, because cigars, too, can do harm. If regulators determine that premium cigars do not pose the same public health risks as other products, they can keep the demands on their manufacturers relatively light.

But for one product there is good reason for caution. E-cigarettes, which deliver a nicotine-laced vapor that presumably contains many fewer harmful ingredients than tobacco smoke, could help addicted, lifetime smokers to reduce their consumption or quit. On the other hand, e-cigarette use among young people is soaring, and there is concern that it might be a gateway to conventional smoking. In addition, some adult smokers may use e-cigarettes to augment their traditional cigarette habit when they otherwise might have kicked it.

Unlike with many other nicotine-containing products, the FDA has to determine how to keep e-cigarettes available to those who might benefit from them while minimizing their capacity to hook young people or encourage continued smoking. Thursday's announcement is just the beginning of that process.